Conventionally, to suppress damage due to harmonic components included in the power supply current, internationally regulations are provided on the electronic devices which generate a harmonic current. To clear this regulation, there are policies which perform the power short-circuit by performing the chopping of AC or DC using a converter, and suppress the harmonic current included in the power supply current.
In a converter which performs the chopping of DC, there is an interleave type converter in which a plurality of chopper circuits is connected in parallel and is switched at each of the different switching phases to cancel the ripple caused by the switching in the input current as the sum of the current flowing in each chopper circuit unit, thereby suppressing the harmonic current. In this type, a technique for achieving a loss reduction by bypassing a chopper circuit with a relay is disclosed (for example, see Patent Literatures 1 and 2).